I was riding back here in Maryland in 30* weather with a LS UnderArmor Cold Gear + LS shirt + Fox trooper jacket and shorts, I was fine after warming up. My hands were what got cold. But I don't think you'll need to go that far.

wool

Merino wool is the best. Get a shirt and socks. Then all you need is a light shell and vest for Arizona. Ibex sells great knee warmers and they go on sale at the end of the season. Use the thinnest wool layer for biking, thicker layers are too warm for a sport that is this aerobic. My Patagonia wool shirt is a great base layer but slightly itchier than Ibex wool. Icebreaker and Smartwool are excellent quality, IO Bio, new out of Canada, I haven't tried.
Wool keeps you warm when wet and is best at keeping you comfortable over a much wider range of tempratures than any synthetic. You have to try it to understand. Usually feel slightly cool, rarely hot, perfect.
Been a skier for decades and now that I finally strated wearing a merino base layer I'm always comfortable from the lifts to the lodge.
With capilene I was always hot and cold, not as comfortable.

If you live in Phoenix and it's only 70° out, you're gunna need tights, winter-boots, face-mask, and some sort of waterproof jacket.

If you live in Prescott and it's only 50°, shorts, some sort of wool socks, and maybe a long sleeve jersey.

LOL we're built for heat down here, don't make fun of us!

I’m a wuss in cold. I wear my LS under armour cold weather at this time of year, love it! Plus tights and a windbreaker over. Actually I wear cold weather stuff as soon as it starts getting chilly, 60s or so. Yes, 60s, brrrrr cold! I've considered that face mask thing but I couldn't get past how ridiculous I'd look riding around Phoenix in it! Oh and I have some heavy gloves for the really cold days when it’s in the 50s outside…….

I may take flak for this and truly hate to offend anyone, but Jayem is right!! Although I have gotten softer since moving from Buffalo, NY to Preskit, LOL........ I must tell you though, my ride last week Tuesday right before then rain on BCT at 75 degrees felt pretty good!!!!